Treating glass sheets



Dec. 22, 1964 R. ROBINSON TREATING GLASS SHEETS Filed May 18, 19

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mam/saw United States Patent 3,162,520 TREATING GLASS SHEETS Lee R. Robinson, Tarentum, Pa., assignor to Pittsburgh Plate Glass Company, Allegheny County, Pa., :1 corporation of Pennsylvania Filed May 18, 1959, Ser. No. 814,081 3 Claims. (Cl. 65-104) The present invention relates to treating glass sheets, and specifically relates to bending glass sheets into shapes having a substantially fiat main portion and an end portion bent about an axis oblique to the longitudinal axis of the main portion and tempering sheets so shaped while they are still hot from their bending operation.

Recently, station wagons have been modified in style so that their tempered rear side lights have included an integral portion bent to the rear of the vehicle. Since the rear of the vehicle extends upwardly at an oblique angle, the rear of the side light has to be bent about an oblique axis of non-uniform curvature relative to the longitudinal axis of its main portion which extends in a vertical plane along the side of the vehicle when installed. Thus, it is necessary to bend the glass sheet to form a so-called conical bend of varying radius of curvature instead of the modified cylindrical bends of non-uniform radius of curvature previously required of continuous wrap-around Windshields and backlights.

When such conical bends for station wagon lights were first demanded by the automotive industry, the only apparatus available to applicants assignee thought capable of performing this bend was a small furnace and tempering apparatus of a size capable of handling one sheet at a time. Since this furnace could not possibly produce the high production requirements of the customer, another solution considered involved construction of a specialized lehr and tempering apparatus for this particular part involving an expenditure on the order of half a million dollars. At this time, other mass production tempering equipment suitable for bending glass sheets to sharp bends at both ends and tempering the bent sheets to produce backlights was not being fully exploited because of a drop in automobile demand.

The present invention enables the fabrication of bent, tempered rear side windows on a mass-production tempering line primarily designed for backlights having both extremities bent relative to a main central portion and avoids the use of low production facilities or the expenditure of tremendous sums of money for producing a specialty item whose popularity may be temporary.

The present invention involves orienting a fiat glass sheet to be bent to a conical bend in a horizontal plane so that its oblique bending axis is parallel to a horizontal linear path of movement taken by the sheet moving through a bending furnace and tempering apparatus. The bending furnace comprises heating elements controlled to provide a longitudinally and transversely varying temperature pattern including a line of heating elements energized to produce a line of maximum temperature parallel to the linear path of movement. The oblique bending axis that is desired for the glass sheet is also aligned with the line of heating elements providing the line of maximum temperature.

This orientation of the sheet relative to the linear path of movement is maintained while moving the sheet through the bending furnace along the linear path of movement. Furthermore, this orientation is also maintained when the bent glass is passed between spaced, opposed blasts of tempering fluid provided by tempering apparatus.

The latter includes sets of upper and lower nozzles or slots arranged to provide an arcuate space for receiving 3,162,520 Patented Dec. 22, 1964 the bent glass sheet. This arcuate space is substantially elliptical in cross section and of modified cylindrical shape of non-uniform radius of curvature.

By maintaining the oblique orientation of the glass sheet relative to its longitudinal axis after the latter is conically bent, the bent sheet presents an elevation in a plane normal to the linear path of movement that conforms to the elliptical cross section of the space provided between the tempering nozzles. Therefore, each portion of the glass sheet surfaces is maintained a distance from a nozzle orifice providing the origin of its impinging tempering fluid blast that is substantially equal to that of every other portion of the curved glass sheet from its adjacent nozzle orifice throughout the curved space between the spaced nozzle sets.

If the bent sheet is not cocked relative to its linear path of movement, complicated movements to change settings for the nozzles of each nozzle set would be required for each pattern instead of the relatively simple expedient of the present invention that provides a slightly different cocking angle, slightly different heating control arrangement and slightly different arrangement of elliptical spacing between nozzle sets, all of which are accomplished more easily than complicating the arrangements of the nozzles to conical patterns and conical movements in addition to varying the heating control arrangement, when production patterns are changed.

In order to understand the present invention more fully, an illustrative embodiment will now be described. In the drawings which form part of the description,

FIGURE 1 is a longitudinal plan view, partly in section and mostly schematic, of apparatus utilizing the present invention for bending and tempering glass sheets.

FIGURE 2 is an end view of a flat glass sheet supported for bending in a bending furnace and taken along the lines I'[lI of FIGURE 1.

FIGURE 3 is another end view of a bent glass sheet supported after bending and located between upper and lower sets of nozzles and taken along the lines III--III of FIGURE 1 showing how the bent glass sheet presents an elliptical rather than a conical shape in a plane normal to its linear path of movement between the nozzles even though the glass has been bent into a conical bend.

FIGURE 4 is a plan view of a glass sheet bent according to the requirements of the present invention.

FIGURE 5 is a side elevation of the conically bent glass sheet shown in FIGURE 4.

Referring to the drawings, reference number 10 refers to a loading station wherein glass sheets 11 precut to outline are mounted on a bending mold 12 supported on an open frame carriage 14 having diagonally extending support bars 15 within the carriage frame for supporting a bending mold thereon in a manner to be described in more detail later.

A stub roll conveyor 16 extends sequentially from the loading station 10 through a furnace 18, a tempering station 20, and cooling stations 22 to an unloading station 24. The mold support carriage 14 is provided with spaced, parallel runners 26 that ride on the stub rolls of the stub roll conveyor 16. The spaced runners 26 of each carriage 14 are interconnected to each other near their leading and trailing edges by shaped connecting rails 27.

The furnace 18 is in the form of a tunnel having entrance and exit doors which are actuated by a timing sequence controlled by the passage of the carriages 14 through the bending furnace 18. Since this control forms no part of the present invention, it will not be described in detail.

Overhead heaters 28 and bottom heaters 30 are disposed in side-by-side relation to form a series of longitudinally adjacent rows above and below the path of movement taken by the carriages 14 along stub roll conveyor 16. Heaters 28 and 30 radiate heat onto glass sheets 11 on molds 12 which are supported in obliquely oriented relation to the carriages 14. Each of the overhead heaters 28 and bottom heaters 30 is controlled individually to provide a heating pattern both longitudinally and transversely of the path of'movement taken by the glass sheets through the bending furnace 18. At least one overhead heater 29 and one bottom heater 31 aligned in a vertical plane with the overhead heater 29 in each row of heaters is energized more than the remaining heaters of the row so as to radiate maximum energy along a longitudinal line provided by the aligned heaters 29 and 31. Additional heaters 29 and 31 are aligned in lines parallel to the path traversed by the glass sheets through the furnace 18 so that these heaters 29 and 31 form lines of intense radiant heat sources to irradiate the portion of the glass sheet to be bent most severely from above and below along the axis of bending oblique to the longitudinal axis of the elongated glass sheet.

The molds on which the glass sheets are bent are conventional sectionalized skeletonized tempering stainless steel molds comprising a pair of relatively rotatable sections. Each of the sections comprises edgewise disposed rails that are apertured to permit the escape of tempering fluid after it impinges on the glass sheet for the tempering operation. The upper edges of the mold rails may be serrated or notched either as a substitute for the apertures or in addition to the apertures.

The particular mold construction shown comprises a mold section 32 having saddles or inverted channel members 33 attached to the bottom of the mold section in laterally spaced pairs and extending downwardly to rest loosely on the diagonal mold support bars forming part of carriage 14. The loose fitting is necessary to prevent mold warpage from differences in thermal expansion and contraction between the mold and the carriage during temperature changes that are incidental to the bending cycle. In other words, the saddles 33 serve as means attached to the bending mold which cooperate with the mold support means provided by the bars 15 to support the mold 12 at an oblique angle relative to the carriage support runners 26 in a substantially horizontal plane within the carriage frame defined by runners 26 and shaped rails 27 and above the carriage support plane defined by the spaced parallel runners 26.

The oblique orientation of the mold relative to the carriage may also be obtained by having support bars extend parallel to the runners and having the saddles 33 of each pair arranged in obliquely spaced relation to each other on opposite sides of the mold. The oblique line between the pair of saddles in the latter case should be substantially parallel to the oblique axis of sharpest bending.

The mold section 32 is provided with rails whose upper edge 34 provides a substantially flat shaping surface for supporting a portion of the glass sheet. The mold also comprises a pivotable mold section 36 having attached thereto at its outboard extremity a glass edge support member in the form of a plurality of spaced fingers 37 which are adapted to support a longitudinal extremity of a flat glass sheet by contacting the latter at its bottom surface. The mold section 36 is formed of an edgewise disposed rail whose upper edge 38 forms a curved portion of the upper shaping surface of the bending mold 12.

The pivotable mold section 36 is pivoted relative to mold section 32 by means of hinges 40 attached to mold section 32 and counterweighted lever arms 42 attached to the pivotable mold section 36 and pivotable about hinges 40.

The center of gravity and mass of the lever arms 42 and that of the pivotable mold section 36 is arrarnged in such a manner that the counterweighted mold section 36 tends to rotate into a closed mold position shown in FIG- URE 3. However, when a flat glass sheet rests upon the mold, the mass of the flat glass sheet extermity resting on the closely spaced support fingers 37 counterbalances the tendency of the counterweighted lever arms 42 to rotate the pivotable mold section 36 into the closed mold posi tion about hinges 40 until such time as the glass is softened by heat. A stop member 43 is located in the path of rotation of the extremity of each lever arm 42 beyond the counterweight so that further rotation of the lever arm is prevented when the counterweighted lever arm 42 rotates to contact the stop member 43. a

End stops 44 are located immediately outboard of the outboard longitudinal extremity 46 of the mold section 32 to prevent the glass from sliding longitudinally of the mold when the pivotable mold section 36 rotates into its closed mold position. One or more side stops 47 are located laterally outboard to one or both sides of the mold adjacent mold extremity 46 to insure proper lateral registry of the fiat glass on the mold.

An illustrative tempering station 20 comprises a plurality of upper nozzle members 48 flanked by upper pivotable wing boxes 50 and lower nozzle members 52 flanked by lower pivotable wing boxes 54. When the orifices of the upper and lower nozzles carried by the upper nozzle members 48, upper pivotable wing boxes 50, lower nozzle members 52 and lower pivotable wing boxes 54 form a curved space 58 having a modified cylindrical cross-section extending transversely of the linear path of movement 56 provided by the stub roll conveyor 16. Means is provided to move the nozzles in unison in closed orbital paths along the surfaces defining the boundaries above and below the curved space 58.

The glass sheet 11 as shown in FIGURES 4 and 5 comprises a substantially fiat main portion 60 and an end portion 62 forming a conical bend of non-uniform radius of curvature relative to the main portion 60. The bend of non-uniform radius of curvature includes an axis 64-64 connecting the points of sharpest curvature which extends obliquely across the sheet.

A conventional method of bending and tempering elongated glass sheets has been to mount glass sheets 11 on successive bending molds 12 and to convey the glass laden molds along a linear path of movement 56 through a hot atmosphere provided by a bending furnace 18. When the hot atmosphere softens the glass sheets sufficiently, the counterweighted lever arms 42 urge the mold section 36 to pivot upwardly into the closed mold position, thereby impressing the shape of its upper edge 38 onto the end portion 62 of the glass sheet to cause the latter to assume its desired shape.

Subsequently, each successive bent glass sheet is chilled at the tempering station 20 while still mounted on the mold by exposing its surfaces to opposed blasts of tempering fluid, such as air blasts. The blasts are moved in closed orbital paths relative to the surfaces and are imparted from the spaced opposed sets of nozzle orifices spaced equal distances from each other and substantially uniformly spaced from the glass sheet surfaces. The orbital paths of adjacent nozzle blasts overlap each other to cover the entire glass sheet surfaces. The glass sheet is then cooled to handling temperatures at cooling stations 22 before it is unloaded from the mold at the unloading station 24.

Instead of conveying the glass sheets and their supporting molds along paths of movement parallel or normal to the longitudinal axis of the elongated sheet to be bent as has been traditionally done in the past, the present invention proposes to mount the bending mold 12 upon the carriage 14 in such a manner that its horizontally supported fiat glass sheet 11 is cocked at an angle to the path of movement taken by the glass sheet along the conveyor 16. Specifically, the glass sheet is oriented so that the axis 64-64 interconnecting the points of sharpest bending is disposed parallel to the linear path of movement 56 and is aligned with the line of maximum temperature provided by the heating elements 29 and 31 which are energized to impart a line of maximum heat intensity parallel to the path of movement 56.

When the mold sections move into the closed mold position to impart a conical bend to the glass sheet by a combination of heat sagging and mechanical forces, the curved glass sheet present a modified cylindrical crosssection in a plane transverse to its path of movement 56. Consequently, when it reaches the tempering station 20, it presents an elevational curve that is properly aligned with the curved space 58 between the upper and lower nozzle members and wing boxes provided with nozzles 48, 50, 52, and 54, respectively. Thus, when tempering fluid blasts are imparted onto the opposite surfaces of the bent glass sheets through the spaced set of opposing nozzles, the different portions of the susface of the curved glass sheet 11 are equally quenched and the glass sheet is uniformly tempered throughout its extent without requiring any complicated arrangement of nozzles to compensate for the conical curvature of the bent glass sheet.

The present description has been for the purpose of illustration rather than limitation. For example, the car riages 14 may be provided with support bars 15 that extend transversely rather than diagonally thereacross and molds for patterns involving different conical bending angles may be cocked properly by locating oppositely spaced saddles or loosely fitting channel members 33 diagonally of each other rather than normal to the molds longitudinal axis. Furthermore, the support rods can be made part of the mold structure to be supported in cocked relation on the carriage without departing from the present invention. Displacement of the axis of sharpest bend from the location illustrated is accomplished by varying the heat pattern from heating elements 28 and 30.

Other obvious alternatives involve the tempering apparatus employed. For example, cocking the fiat glass sheets relative to the path of movement so that the concially bent glass sheets are maintained with their axis 64-64 parallel to their linear movement path 56 is equally susceptible of use when the glass is tempered between blasts emanating from upper and lower slots instead of nozzles. The slots may be curved transversely of the path of movement and extend normally to the path of movement as disclosed in US. Patent No. 2,646,647 to William P. Bamford et al. or may be disposed parallel to the path of movement 56 to cover the entire glass sheet as disclosed in US. Patent No. 2,881,565 to Gerald White, for example.

What is claimed is:

1. In a method of bending and tempering elongated glass sheets into a shape having a substantially fiat elongated main portion and only one end portion bent about an axis connecting points of sharpest curvature extending oblique to the longitudinal axis of said main portion wherein an unbent glass sheet is supported in bending relation to a shaping surface, conveyed along a linear path of movement through a hot atmosphere having a temperature sufiicient to soften the glass for a period of time sufiicient for the glass to attain its softening temperature, force is applied to the heat-softened glass sheet to help conform the latter to said shaping surface, and the surfaces of the bent sheet are suddenly chilled by exposing the surfaces of the bent sheet to opposing blasts of tempering fluid blasted from spaced, opposed sets of nozzles having orifices arranged along opposite sides of a curved space of substantially cylindrical cross-section having a non-uniform radius of curvature transversely of said linear path of movement by causing the bent glass sheet to occupy said transversely curved space while exposing the heated, bent glass sheet surfaces thereto, the improvement comprising supporting an elongated fiat glass sheet to be bent to said shape in a substantially horizontal plane; orienting the glass sheet so that its oblique bending axis connecting said points of sharpest curvature is parallel to said linear path of movement;

maintaining said horizontal support and said orientation of said sheet relative to said linear path of movement while moving said sheet through said hot atmosphere along said linear path of movement to cause the end portion of the glass sheet to be bent about said axis oblique to the longitudinal axis of said main portion; and continuing to maintain the oblique orientation of the sheet after it is bent so that the bent sheet presents a substantially cylindrical cross-sectional shape of nonuniform radius of curvature transversely of said linear path of movement that substantially conforms in elevation and curvature to said curved space when occupying said curved space between said spaced, opposed orifices of said nozzles.

2. In a method of fabricating bent, tempered glass sheets from unbent elongated sheets precut to outline, wherein each sheet is bent into a shape having a substantially fiat main portion and only one end portion bent relative to said main portion to provide a bend of non-uniform radius of curvature, with the bend of nonuniform radius of curvature including the axis connecting the points of sharpest curvature extending obliquely across the sheet by conveying the unbent sheet while supported in bending relation to a shaping surface along a linear path of movement through a hot atmosphere providing a temperature pattern both transversely and longitudinally of the path of movement and including a line of maximum temperature parallel to said linear path of movement to cause the heated glass sheet to sag into conformance with said shaping surface and exposing the surfaces of the bent glass sheet to opposed blasts of tempering fluid imparted through spaced, opposed sets of nozzles having orifices arranged along opposite sides of a curved space of substantially cylindrical crosssection having a non-uniform radius of curvature transversely of said linear path of movement by causing said heated, bent glass sheet to occupy said transversely curved space while exposing said glass sheet surfaces to said blasts, the improvement comprising supporting the elongated flat glass sheets in a substantially horizontal plane; orienting said sheets so that said axis connecting the points of sharpest curvature is parallel to said linear path of movement and aligned with said line of maximum temperature; maintaining said horizontal support, alignment and orientation of said sheet relative to said linear path of movement while moving said sheets through said hot atmosphere along said linear path of movement to cause the glass sheets to be bent about said obliquely extending axis and continuing to maintain the orientation of each sheet after it is bent so that the bent sheet presents a curved shape of substantially cylindrical crosssection having a non-uniform radius of curvature transversely of said linear path of movement that substantially conforms in elevation and curvature to said curved space when occupying said curved space provided by said spaced, opposed orifices of said nozzles.

3. Apparatus for bending glass sheets into a shape comprising a substantially flat main portion and only one end portion bent about an axis oblique to the longitudinal axis of the main portion and tempering the bent glass sheet comprising a tunnel-like furnace, tempering apparatus, a conveyor extending through said furnace and tempering apparatus to define a linear path of movement therethrough, said tempering apparatus comprising upper and lower nozzles defining a space of substantially cylindrical cross-section having a non-uniform radius of curvature transversely of said linear path of movement, a bending mold having an upper shaping surface conforming in elevation and outline to the shape desired for a bent glass sheet, an open frame carriage comprising spaced, parallel carriage support runners adapted to extend parallel to said linear path of movement, mold support means attached to said carriage, and means attached to said bending mold and cooperating with said mold support means to support the bending mold in a horizontal plane at an oblique angle relative to the carriage support runners, said angle being of a size to cause said oblique axis to be substantially parallel to said linear path of movement defined by said conveyor. 5

References Cited in the file of this patent UNITED STATES PATENTS 2,240,349 Preston Apr. 29, 1941 10 2,293,537 Ferlito Aug. 18, 1942 2,536,905 Bird et a1. Ian. 2, 1951 2,551,606 Iendnsak May 8, 1951 2,560,305 Ramain July 10, 1951 2,646,647 Bamford et al. July 28, 1953 15 8 Reggiani Apr. 6, 1954 Bird et a1 May 11, 1954 Grotefeld June 15, 1954 Black Feb. 28, 1956 Black Sept. 10, 1957 McRoberts et a1. Mar. 10, 1959 Golightey et a1. Mar. 10, 1959 Fowler et a1. Aug. 4, 1959 FOREIGN PATENTS Great Britain Nov. 14, 1951 Canada Oct. 30, 1956 Australia Mar. 18, 1958 Canada Sept. 23, 1958 France Ian. 20, 1958 UNITED STATES PATENT OFFICE nETmcArE or be Patent No, 3,162,520

It is hereby certified that ent requiring correction and that corrected below.

Column 6,

ECTIQN Lee RC. Robinson line 21, for "the axis" read M an axis December 22, 1964 Signed and sealed this 28th day of June 1966 c i (SEAL) Attest:

ERNEST W. SWIDER Attesting Officer Enw :-t r J. BRENNER.

Commissioner of Patents 

1. IN A METHOD OF BENDING AND TEMPERING ELONGATED GLASS SHEETS INTO A SHAPE HAVING A SUBSTANTIALLY FLAT ELONGATED MAIN PORTION AND ONLY ONE END PORTION BENT ABOUT AN AXIS CONNECTING POINTS OF SHARPEST CURVATURE EXTENDING OBLIQUE TO THE LONGITUDINAL AXIS OF SAID MAIN PORTION WHEREIN AN UNBENT GLASS SHEET IS SUPPORTED IN BENDING RELATION TO A SHAPING SURFACE, CONVEYED ALONG A LINEAR PATH OF MOVEMENT THROUGH A HOT ATMOSPHERE HAVING A TEMPERATURE SUFFICIENT TO SOFTEN THE GLASS FOR A PERIOD OF TIME SUFFICIENT FOR THE GLASS TO ATTAIN ITS SOFTENING TEMPERATURE, FORCE IS APPLIED TO THE HEAT-SOFTENED GLASS SHEET TO HELP CONFORM THE LATTER TO SAID SHAPING SURFACE, AND THE SURFACES OF THE BENT SHEET ARE SUDDENLY CHILLED BY EXPOSING THE SURFACES OF THE BENT SHEET TO OPPOSING BLASTS OF TEMPERING FLUID BLASTED FROM SPACED, OPPOSED SETS OF NOZZLES HAVING ORIFICES ARRANGED ALONG OPPOSITE SIDES OF A CURVED SPACE OF SUBSTANTIALLY CYLINDRICAL CROSS-SECTION HAVING A NON-UNIFORM RADIUS OF CURVATURE TRANSVERSELY OF SAID LINEAR PATH OF MOVEMENT BY CAUSING THE BENT GLASS SHEET TO OCCUPY SAID TRASNVERSELY CURVED SPACE WHILE EXPOSING THE HEATED, BENT GLASS SHEET SURFACES THERETO, THE IMPROVEMENT COMPRISING SUPPORTING AN ELONGATED FLAT GLASS SHEET TO BE BENT TO SAID SHAPE IN A SUBSTANTIALLY HORIZONTAL PLANE; ORIENTING THE GLASS SHEET SO THAT ITS OBLIQUE BENDING AXIS CONNECTING SAID POINTS OF SHARPEST CURVATURE IS PARALLEL TO SAID LINEAR PATH OF MOVEMENT; MAINTAINING SAID HORIZONTAL SUPPORT AND SAID ORIENTATION OF SAID SHEET RELATIVE TO SAID LINEAR PATH OF MOVEMENT WHILE MOVING SAID SHEET THROUGH SAID HOT ATMOSPHERE ALONG SAID LINEAR PATH OF MOVEMENT TO CAUSE THE END PORTION OF THE GLASS SHET TO BE ENT ABOUT SAID AXIS OBLIQUE TO THE LONGITUDINAL AXIS OF SAID MAIN PORTION; AND CONTINUING TO MAINTAIN THE OBLIQUE ORIENTATION OF THE SHEET AFTER IT IS BENT SO THAT THE BENT SHEET PRESENTS A SUBSTANTIALLY CYLINDRICAL CROSS-SECTIONAL SHAPE OF NONUNIFORM RADIUS OF CURVATURE TRANSVERSELY OF SAID LINEAR PATH OF MOVEMENT THAT SUBSTANTIALLY CONFORMS IN ELEVATION AND CURVATURE TO SAID CURVED SPACE WHEN OCCUPYING SAID CURVED SPACE BETWEEN SAID SPACED, OPPOSED ORIFICES OF SAID NOZZLES.
 3. APPARATUS FOR BENDING GLASS SHEETS INTO A SHAPE COMPRISING A SUBSTANTIALLY FLAT MAIN PORTION AND ONLY ONE END PORTION BENT ABOUT AN AXIS OBLIQUE TO THE LONGITUDINAL AXIS OF THE MAIN PORTION AND TEMPERING THE BENT GLASS SHEET COMPRISING A TUNNEL-LIKE FURNACE, TEMPERING APPARATUS, A CONVEYOR EXTENDING THROUGH SAID FURNACE AND TEMPERING APPARATUS TO DEFINE A LINEAR PATH OF MOVEMENT THERETHROUGH, SAID TEMPERING APPARATUS COMPRISING UPPER AND LOWER NOZZLES DEFINING A SPACE OF SUBSTANTIALLY CYLINDRICAL CROSS-SECTION HAVING A NON-UNIFORM RADIUS OF CURVATURE TRANSVERSELY OF SAID LINEAR PATH OF MOVEMENT, A BENDING MOLD HAVING AN UPPER SHAPING SURFACE CONFORMING IN ELEVATION AND OUTLINE TO THE SHAPE DESIRED FOR A BENT GLASS SHEET, AN OPEN FRAME CARRIAGE COMPRISING SPACED, PARALLEL CARRIAGE SUPPORT RUNNERS ADAPTED TO EXTEND PARALLEL TO SAID LINEAR PATH OF MOVEMENT, MOLD SUPPORT MEANS ATTACHED TO SAID CARRIAGE, AND MEANS ATTACHED TO SAID BENDING MOLD AND COOPERATING WITH SAID MOLD SUPPORT MEANS TO SUPPORT THE BENDING MOLD IN A HORIZONTAL PLANE AT AN OBLIQUE ANGLE RELATIVE TO THE CARRIAGE SUPPORT RUNNERS, SAID ANGLE BEING OF A SIZE TO CAUSE SAID OBLIQUE AXIS TO BE SUBSTANTIALLY PARALLEL TO SAID LINEAR PATH OF MOVEMENT DEFINED BY SAID CONVEYOR. 